The present invention relates to a spatial guide and support for attachment to a line trimmer.
A conventional line trimmer 60 in accordance with the prior art shown in FIG. 9 comprises a handle 61, a support rod 63, a roller 64, a rotatable cutter head 62, and a cutting string 621. However, the cutting string 621 cannot exactly align with the cutting line of the lawn so that the cutting string 621 easily cuts expensive plant when it is cutting weeds around the plant. In addition, when the conventional line trimmer 60 is used to trim the weeds adjacent to a step of the house, the cutting string 621 easily strikes the step, thereby wearing the cutting string 621. Further, the conventional line trimmer 60 cannot be used to perform an upright cutting and trimming function.
The closest prior arts of which the applicant is aware are disclosed in the following patent documents:
1. U.S. Pat. No. 4,922,694 to Emoto.
2. U.S. Pat. No. 4,981,012 to Clabom.
3. U.S. Pat. No. 5,095,687 to Andrew et al.
4. U.S. Pat. No. 5,107,665 to Wright.
5. U.S. Pat. No. 5,317,807 to Pulley.
6. U.S. Pat. No. 5,940,973 to Kitz.
7. U.S. Pat. No. 5,996,234 to Fowler et al.
In accordance with one aspect of the present invention, there is provided a spatial guide and support for attachment to a line trimmer comprising a rotatable cutter head including a lawn cutting string mounted thereon and a main shaft extending upward therefrom; a moving member mounted on the main shaft of the cutter head for moving the cutter head and including a fastener secured on the main shaft of the cutter head; an auxiliary member mounted on the main shaft of the cutter head and including a mounting bracket rotatably mounted on the fastener of the moving member, a guide track secured on the mounting bracket, and an auxiliary moving wheel adjustably mounted on the guide track; and an adjusting member mounted on the mounting bracket of the auxiliary member for releasably securing the mounting bracket on the fastener of the moving member.
The fastener of the moving member includes a first clamping block mounted on the main shaft, and a second clamping block secured to the first clamping block with the main shaft secured between the first clamping block and the second clamping block. The first clamping block has two sides each provided with an arcuate first piece transversely defining an elongated slide groove, and the second clamping block has two sides each provided with an elongated rib secured in the slide groove, and an arcuate second piece extending from the second clamping block and mating with the first piece of the first clamping block.
The first piece of each of the two sides of the first clamping block defines a plurality of first positioning holes, the second piece of the second clamping block defines a plurality of second positioning holes mating with the first positioning holes, the auxiliary member further includes an upright support post secured on the mounting bracket to rotate therewith and defining an insertion hole, and the adjusting member includes a press plug secured on a top portion of the support post, a control rod slidably mounted in the insertion hole of the support post and having an upper end extending through the press plug and defining a through bore, a mediate portion provided with an annular shoulder, and a lower end detachably inserted into one of the first positioning holes and the second positioning holes, a pull ring secured to the through bore of the control rod, and a biasing member mounted on the control rod and biased between the annular shoulder and the press plug.
In operation, the pull ring can be moved upward to move the control rod upward, thereby detaching the lower end of the control rod from the second positioning hole so that the mounting bracket is rotatable relative to the second piece of the second clamping block. In such a manner, the guide track together with the auxiliary moving wheel can be rotated with the mounting bracket so that the angle of the auxiliary moving wheel can be adjusted so as to efficiently achieve a lawn trimming function.
The guide track has two sides each defining a plurality of positioning slots, and the auxiliary moving wheel includes two elastic strips each slidably mounted in the guide track and each having an outer side provided with an insertion block detachably received in one of the positioning slots of a respective one of the two sides of the guide track and an inner side provided with a press block protruding upward.
An object of the present invention is to provide an auxiliary moving wheel whose angle and length can be properly and easily adjusted according the user""s stature, thereby efficiently achieving the lawn trimming effect.
Another object of the present invention is to provide an auxiliary moving wheel which can move along the edge of the step or the plant so that the lawn cutting string can easily cut the weeds along the edge of the step or the plant without a possibility of cutting the plant or wearing the lawn cutting string by the step, thereby efficiently protecting the plant and the lawn cutting string.
A further object of the present invention is to provide an auxiliary moving wheel which can provide a slidable and alignable function so that the lawn cutting string aligns with the auxiliary moving wheel without incurring deviation, thereby preventing the lawn cutting string from cutting the plant.
A further object of the present invention is to provide an auxiliary moving wheel which can be moved on the lawn for supporting the moving member and the cutter head so that the lawn cutting string can be used to perform an upright cutting and trimming function.